The raw data are continuously archived at the BeppoSAX mission SOC, in the form of a compressed unique telemetry file for each orbit. The GRBM hardware team, through a PC Linux workstation installed directly at SOC, can access a local
machine in which the last 20 orbits data are archived. The data can be retrieved via ftp from the PC Linux workstation.
The specific PDS/GRBM data files are unpacked from the telemetry file using a
program specifically implemented by the GRBM hardware group. Finally, GRBM 1s ratemeters and energy spectra in XAS format are obtained by running XAS/PDS prototype programs, which allow the choice of the time interval in which the ratemeters are accumulated and of the 128s spectral packet(s) to be accumulated.
The time associated to each 1s ratemeters bin (corresponding to the end of the corresponding time interval) and to the start and end of each spectral packet is given in On-Board Time (OBT). The OBT can be converted in Universal Time (UT) by means of the OBT-UT time synchronization file, which is part of the set of files produced by the unpacking program.
For each trigger that has occurred during the relevant orbit, the trigger time
in OBT can be read from one of the HRTP (see section 1.2.4) packet by means
of a specific program developed in PERL language by the GRBM team, which also converts
it in UT. Finally, the HRTP are converted in ASCII files using the programs
described in section 1.2.4.